Just bought industrial grade SD cards for Siemens PLCs the other day, almost $2k for 32 gig and due to certification for safety only good for ten years regardless of condition/use.
Equivelents spec cards without the magic S word on them are still around $800.
They are actually a different kind of memory used, so I guess not manufactured in same consumer number quantities.
I always liked the look of something like puppy Linux that loaded to ram, pretty sure most Linux variants allow this as an option, that would potentially make use of consumer grade palletable.
1. Buy high quality SD cards
2. Remove as much disk-IO as possible, using an external USB stick for raw data storage, logs, swap, etc
3. If you really need to make it stable, make the OS read-only
Aside from USB sticks, any ideas on alternative storage suitable for RPis (something small)? I know you can get eMMC modules that fit into the SD card slot, but I would have guessed they'd have the same issue with writes.
They are indeed using UPS', and the workloads naturally have a low write load.
I decided to do this with RPi and went through several revisions as I learned/relearned a lot about Linux. The first version was built on full Raspbian and added a basic server listening on some port or another so I could remotely reboot the things by clicking links on a simple website I put together. That build would usually crap out after a few months and the Pis would stop booting fully from the Sandisk MicroSD cards.
Most recent rev was built from the "Lite" version of Raspbian as I was looking to stay slim and have less stuff to update/run in the background/cause issues with the basic operation of a device that only needed to boot, load Chromium, and open a webpage defined in the startup script.
Those have been a lot more stable (no more reimaging a card here and there every month or two) but they still occasionally crap out and a reimage is the only option (maybe once every 6-8 months). This is in an air conditioned building with stable power, wired LAN connection, and fast SD cards. I can't imagine they would be even this reliable running all the time in any sort of "hostile" environment or even using wireless networking.
I looked into network boot but didn't really have the time or resources to set it all up on the school's network.
